Resilient wheel for vehicles



July 21, 1936. E. H. SOUTH RESILIENT WHEEL FOR VEHICLES Filed March 20, 1935 2 Sheets-Sheet 1 Ernest Hcmllton south 0& 01M

Attor'ne ys July 21, 1936. E. H. SOUTH 2,048,575

RESILIENT WHEEL FOR VEHICLES Filed March 20, 1935 2 SheetsSheet 2 Qwucmlm Patented July 21, 1936 PATENT OFFICE RESILIENT WHEEL FOR VEHICLES Ernest Hamilton South, Salisbury, Southern Rhodesia Application March 20, 1935, Serial No. 12,093

In Great Britain August 2, 1933 6 Claims.

This invention relates to resilient wheels for vehicles, of the kind in which a resilient outer suspension ring or annulus is connected with an inner rigid rim or the like of less. diameter which is concentric therewithwhen the wheel is un--' loaded by means which will permit the resilient ring to approach the rigid rim, where it is subject to external pressure, but is adapted to resist movement of the resilient rim away from said rigid rim.

According to the invention a resilient wheel of the kind set forth comprises a hub, a flexible substantially inextensible tread band and a plurality of spokes connecting said hub and band 5 wherein said spokes consist of two or more tubular members, the extension of which is limited by the binding of an outer tubular member upon an inner tubular member. Preferably these spokes are flexibly connected 1 at their ends'with the hub and band respectively, for example, by interposed blocks of India rubber i (which may be suitably reinforced) vulcanized" thereto or by means of ball and socket joints which may be suitably j acketted or sealed to exclude grit and to retain lubricant, or by means of strips diverging from thespokes to the band. Each spoke is preferably constructed of two layers of spring steel ribbon wound helically at a steep angle, and in opposite directions, one layer closely surrounding the other which encloses a third layer which is similar but wound at a small angle and spaced within the second layer (depending upon the degree of extension required). The ends of these three coils are secured both to the hub and band, for example, by extensions of said coils constituting the divergent strips mentioned above, and the arrangement is such that when a spoke is caused to extend, the outer layers decrease in diameter at a greater rate than the third layer and ultimately bind thereon and prevent further appreciable extension. At that part of the wheel, when loaded, where the band is caused to approach the hub, the inherent contracting quality of the spokes reduces their length.

Alternatively, the spokes may be constructed of layers of woven plaited or braided spring wire, and if desired, a core of India rubber may be disposed within said layers of braided wire.

The spokes are preferably covered, for example with India rubber, and may be secured to the hub in or near its central plane and splay outwards in two series towards the edges of the flexible band and if desired a third series consisting of compression springs. may be arranged in said central plane or alternatively an annulus of cellular rubber of approximately triangular section may replace said'third series. This serves to increase the pressure at the centre of the tread and is particularly useful when the wheel 5 passes across a high narrow obstacle such asa high rail when the centre of the rim is caused to assume an inverse curvature.

In the accompanying diagrammatic drawings Figure 1 illustrates the deformation of the wheel under load. Figures: 2 and 3. illustrate in crosssection two formsof wheel according to the invention, and. Figuresi' and 5 are enlarged views of two forms of spokes parts being broken away for the sake of clearness, while Figs. 6' and 7 show the'securement of the individual layersv of the spring steel ribbon to the'hub and the tread band. 7

In Figure l a.is the centre ofthe hub 11 and c is the flexibleband; their relative positions when free and when under load being shown. in full and broken linesirespectively.

Figure 2..shows a loaded wheel with spokes constitutedbyhelically wound strips of. spring steel; ribbon. Each; spoke: is constructed of two layers at and e of; spring. steel ribbon wound helically at a suitable angle, and in opposite directions, the one layer it closely surrounding the other e which encloses a third layer 1 which i preferably stouter and is wound at a smaller 0 angle and spaced within the layer e to an extent depending upon the degree of extension required. The ends of these three coils d, e and ,f are flexibly secured both to the hub b near the medium plane of the wheel, and to the flexible band 0 5 near its edges by ball and socket joints g and the arrangement is such that when a spoke is caused to extend (as at the upper part of Figure 2) the outer layers at and e decrease in diameter at a greater rate than the layer 7 and 40 ultimately bind thereon and prevent further ap-' preciable extension. At that part of the wheel, when loaded, where the band 0 is caused to approach the hub b, as shown at the lower part of Figures 1 and 2, the inherent contracting quality of the spokes reduces their length.

If desired, the ends of the spring steel ribbon constituting the layers :1, e and 1, may be spread out and. secured, for example, by rivets, to the band a. As shown in Figs. 6 and 7, the two outer layers or helixes d and e are bent'in opposite directions while the central layer 1 has its ends cut short and fastened to the two outer layers by means of the bolts or the like. 7

The spokes may be covered with India rubber and an annulus y of cellular rubber of approximately triangular section is arranged between the 7 shown extended and contractedcorrespondingly,

' structed'of layers of helically wound steel ribsplayed spokes; this annulus 7' is shown expanded at the upper part of Figure 2 and compressed atthe lower part thereof, while the spokesare The annulus 7' may be replaced by a seriespof compression springs of approximately triangular section. r

V Figuresr3 and 5 show a similar arrangement except that 'the spokes instead of being conbon are constituted by a layer is of braided spring wire or the like, which may in some cases be disposedoutside a core m of India rubber,'wh.ilst the ends of the'spokes are connected with the hub b and rim 0 by blocks n (Figure 3) of India rubber vulcanized to said parts. If there be no core m provided then the extension of the spoke is limited. 7 by the binding of the strands of the layer is hav' ing a right hand twist upon those having a left hand twist while, if the core. m be'provided' the extension is limited by thecontraction of the layer It onto said core m.

the ground. 7 c

I claim:

1. A resilient wheel comprising a hub, a flexible iresilient substantially inextensible tread band and a plurality of spokes connecting said hub and band, each of said spokes consisting of at least two! resilient members being normally spaced 'apart, the extension of said members being lim- 7 ited by the binding of onemember upon the other.

2. A resilient wheel'com'prising a hub, a flexi 'ble resilient substantially inextensible tread band and a plurality of'spoke's'fiexibly connected at their ends with said hub 'and'said band, each of said spokes consisting of at least two, difieren- V J tially contractible resilient tubular members being normally spaced apart, the extension of said members being limited by the binding of an outer "member. upon an inner member.

3. A resilient wheel comprising a hub, a flexible resilient substantially inextensible tread band and a plurality of spokes connecting said hub and said band, each of said spokes having three coaxially arranged tubular members, each of said members consisting of a layer of spring steel ribbon, the layers of the two outer tubular members being wound helically in opposite directions, the layer of the innermost tubular member being wound helically at a smaller angle than the layers of the two outer' members.

4. A resilient wheel comprising 'a hub, a flexible resilient substantially inextensible treadband, a pluralityof spokes connecting said hub and said band, said spokes spiaying outward in two series from said hub toward the edges of said band, and aresilient annular member between said series connected .with said hub and said band, each of said spokes having at least two differentially contractible'resilient tubular members, said members being. coaxially arranged, the extension'qf said members being limited by the binding of an outer tubular member upon an inner tubular member; s

5. A resilient wheel comprising a'hub, a flexible a resilient, substantially inextensible tread band, a; plurality ofrspokes connecting-said hub and said band, said spokes splaying outward in two series toward the'edges of said band, and resilient means between said series connected with said hub and said band, each of said spokes having at least two differentiallycontractible resilient tubular members, said membersbeing coaxially arranged, the extension of said members being limited by the binding of an outer member upon an inner 35.13 

